The efficacy endpoints will be determined by investigator and subject live assessment of the glabellar rhytids at rest and maximum contraction at each visit (every other day for 6 days post-injection, every month for 9 months following) using a validated 4 point photographic scale (minimal wrinkles [0], mild wrinkles [1], moderate wrinkles [2], or severe wrinkles [3]) used in previous studies. A written description of each photograph will be included to help standardize the application of the Photographic Scale.